Posted
by
samzenpuson Friday April 04, 2014 @05:21AM
from the that's-a-close-one dept.

reifman (786887) writes "Anders Helstrup went skydiving nearly two years ago near Hedmark, Norway and while he didn't realize it at the time, when he reviewed the footage taken by two cameras fixed to his helmet during the dive, he saw a rock plummet past him. He took it to experts and they realized he had captured a meteorite falling during its dark flight — when it has been slowed by atmospheric braking, and has cooled and is no longer luminous."

Article notes that they kept it quiet so the geologists could have a look for the rock - I assume these things are pretty rare and perhaps there's even a concern a treasure hunter might get there first and take it? (perhaps a geologist can give a more informed opinion here....) . Certainly I have a geologist friend who was flown from Europe to the deserts of Australia on more than one occasion to look for meteorites because they are so rare... apparently much easier (comparatively speaking) to spot in a bare desert than lush green European landscapes.

The article suggests they looked for it, couldn't find it, and are now asking the public to help find it. Plus perhaps it took a while before the sky diver realised something had happened after a few views of the footage, he might not have realised at the time.

Article notes that they kept it quiet so the geologists could have a look for the rock - I assume these things are pretty rare and perhaps there's even a concern a treasure hunter might get there first and take it? (perhaps a geologist can give a more informed opinion here....) . Certainly I have a geologist friend who was flown from Europe to the deserts of Australia on more than one occasion to look for meteorites because they are so rare... apparently much easier (comparatively speaking) to spot in a bare desert than lush green European landscapes.

The article suggests they looked for it, couldn't find it, and are now asking the public to help find it. Plus perhaps it took a while before the sky diver realised something had happened after a few views of the footage, he might not have realised at the time.

I'm not a geologist, but I do research on meteorites and have participated in a meteorite search expedition sponsored by the Swiss and Omani governments. You're right: there is a concern that private collectors might find meteorites first. In the case of the expedition I was on, that was a major concern: we were plotting the distribution of thousands of fragments of one meteorite strewn over a large (several hundred square kilometers) area. Each of the fragments we found were photographed where they lay from several angles, the location recorded using GPS, given a catalog number, collected using clean tools etc. Private collectors often don't bother doing this, so it makes it difficult to identify where meteorites in private collections came from. This makes it difficult for researchers who are interested in the precise distribution of the fragments (some of my colleagues are able to use the distribution of light and heavy fragments from this meteorite to determine the speed of the wind at different altitudes when the meteorite passed through the atmosphere, and this requires precise knowledge of where the fragments were found). My particular research is less concerned with location, but it's still nice to know the provenance of meteorites.

Of course, we don't begrudge individuals finding meteorites and wanting to keep or sell them, but we'd really appreciate it if people called their local university (or other relevant authority) so researchers could log the find and perhaps keep a sample for scientific purposes.

There is a similar issue with Civil war artifacts in the US. Relics are worth $$ in the collectors market, but by law you are not allowed to use things like metal detectors on known battlefields. However a couple of years a local guy started doing exactly that. He found, dug up and sold stuff, but with no regards to keeping any records. When he finally got busted the historians didn't know whether to laugh or cry as they now had access to a huge collection of artifacts, but with zero provenance.

Known battlefields? The battle of Westport covered most of south midtown Kansas City. As the civil war was the end of set formation battles I'm sure many battles extended far beyond the official 'battlefields'.

Would make finding old pipes and such a real bitch if metal detectors were banned over large urban areas.

Two years is a long time. It seems it is the time it takes to a non-professional to tamper with a video, after the guy got the idea that the video would be more fun having a meteorite falling along with him. Seriously, a falling meteorite? Even if the camera would have caught a real meteorite, we'd have seen a blurry line, at best. The images breakdown clearly shows a number of photographs that have been added to the video.

If the meteorite and the skydiver were moving at (or near) their respective terminal velocities, why do you think that you'd see only a blurry line? The meteorite is not traveling at orbital velocities that deep into the atmosphere (or else it'd be glowing).

Vertical descent speed under canopy can vary depending on canopy but generally you will see speeds in the range of around 4-6 m/s or 14.4-21.6 kph or 8.95-13.4 mph (unless in an aggressive diving turn, which can increase speeds significantly, but that is not what this jumper was doing).

A spokesdemigod for the Mount Olympus Police Department praised the professionalism of the department's officers who he said had 'acted with restraint' and 'in full compliance with policy' in firing warning shots at a mortal suspected of trespassing and resisting arrest. "Thankfully, deterrence proved sufficient and neither the Olympians nor the interloper were harmed in the encounter."

Every time I hear of a story with insane odds and think just how impossible it is, I'm reminded of just how chaotic things are when playing popular first-person shooters like Black Ops or MW3.

That knife you threw across the map that bounced off the aircraft flying by, hit three rooftops and a radar dish before tumbling down a gutter and catching a rusty nail on a crate just right to flip the knife in the air and kill your opponent from 300 yards away was just as insane with odds.

It happens in good games too. In Counterstrike 1.x, a real headshot from highly explosive grenade is an extremely rare occurrence, I've seen it happen exactly once!It's not just a grenade hitting your face (or head in general), detonation needs to happen at the same time. Enemy player maybe needs to be injured beforehand, as there may be no specific damage value for a grenade headshot. I'm doubting my memory, but I'm pretty sure it happened.

Every time I hear of a story with insane odds and think just how impossible it is,

The thing is that we have human brains evolved to cope with everyday situations. We fail spectacularily at the very small and very large. We fail utterly and catastrophically when those two meet. "Black Swan" is a great book on that topic.

The thing with the highly improbably is the scale at which they happen. We have close to 7 billion people living on that planet. Which - in the words of Tim Minchin - means that one in a million chance events happen all the time.

It's possible that the estimated "one in a million" odds already factor in the whole population, instead of meaning one in a million chance for each person.

Like, if you could estimate that there is a 5% chance that a gold coin burried at a beach will be found ever, that's obviously not per person because after only 20 people walk by, the coin is likely to have been found.

And thus immediately after he explained how people are bad at comprehending the confluence of small probabilities with large numbers, you demonstrate the principle.

Yes, it might be only a 5% chance that _anyone_ finds that gold coin, not 5% chance per person. The issue is that it's not just one gold coin, there are a bunch of gold coins, each of which only has a 5% chance being found. The odds of someone finding a particular coin are small, but the odds of no one finding any of the coins is even smaller.

Life lessons from playing first person shooters... perhaps you need to revaluate your life.

It was an observation and comparison in chance and odds between seemingly impossible events, nothing more. The FPS example is valid if you've ever played one. From the sounds of it, I doubt it.

And the underlying tone that I'm some kind of hardcore gamer that can't pull my head out of a gaming console to "revaulate" my life is far from accurate either, as my FPS observations are from casual play. Like most responsible adults, I hardly have time.

More likely he laid has parachute on the ground for packing and accidentally picked up a rock without noticing and it was ejected when he pulled the chord. They probably can't find the "meteorite" because it's just a rock sitting amongst identical rocks.

There's almost zero indication of the size of the rock in question. The background is clouds and there's no absolute way to tell how close that rock is to the camera lens. Could be 20 feet, could be 2 inches.

Well, we do have size info.
Minimum focal range is approx 23".
Further more, the sensor of a hero 3 has appreox 170 degrees field of view.
Based on this we can know that in order to be in focus at all the object has atleast 0.9 mm/pixel size.
With atleast 12 pixels width that's 10.8mm and at that range/scale the apparant size of it would change dramatically as it passed the fov. It doesn't.

Nobody who packs parachutes calls them 'schutes' so I'm going to go out on a limb and guess you are not a rigger or even a sport jumper:)
There is a lot of bulk compressed into a small space, you can easily not feel an object inside of the parachute when you are packing. Especially if you are packing quickly in order to make a short call to get on the next load.

Because everyone knows that parachutes are ejected with explosive charges, or in the more modern versions, a bottle of compressed air.

No, sport parachutes are deployed by hand either with a pilot chute deployed by hand or by a spring loaded pilot chute deployed by a ripcord. There is an automatic activation device for the reserve parachute that uses a small pyrotechnic charge inside a cylinder that propels a cutter to sever a fabric closing loop that allows a spring loaded pilot chute to deploy.

I have gone skydiving, and the acceleration (or decelaration if you prefer) is rather violent. Without doing the math, I very much doubt that anything would be "popped off the top of the chute".

It could easily happen depending on where the object was. if it was inside of the parachute or inside of the deployment bag.

A rock of that size does not simply find its way into a plane, or into a skydiver's pocket. Gravel-sized rocks, sure. Something the size of your fist? No, just no.

He was first out of the plane but one of only 2 in a wing suit, by the time he opened his chute and the rock fell past the other divers were well below him and you can see where the other wingsuited diver was in the video. Even the plane was below him by this point of the flight. If it came from his chute you'll have to explain to me how it's moving at a few hundred miles per hour relative to him (easily calculated based on frame to frame movement).

Another possible explanation is that the object fell from either the plane or another skydiver (as he was first out of the plane).

Like he explains, and the video clearly shows, when the rock flew past him both the plane and all of the other divers were below him. At the start of the video you can see the plane basically dive past all of the divers and descend below them. He points out where the other divers are, other than one person who enters his airspace about 4 seconds after the rock flies past. It wasn't on the plane, and it wasn't from another diver. They have had 2 years to think about those possibilities. I understand tha

My apologies for showing my ignorance. I watched some videos from a few days before the Slashdot story was posted - they were in a different language than English. I did not know how much analysis had been done (or how long they had been considering the evidence).
I only stated possibilities that seem to have already been disproved. I'm glad you are here for all of us "internet detectives". I don't know what we would do without you doing your own internet detective work.

I am a licensed skydiver and I can tell you that I have seen objects fall out of my canopy on opening and I've seen videos of others that look very similar to this.

It is actually very easy to explain the delay once you understand how modern square ram air parachutes are designed.

Modern canopies are roughly rectangular and are composed of 7 - 9 cells in parallel.

Each cell has an opening at the nose of the canopy that is roughly rectangular. The cell tapers down until the topskin and bottom skin meet at the tail. This creates the parafoil (wing) that looks a lot like an airplane.

On the ground, it is very easy for objects to end up inside of a cell. When you pack the parachute, these objects can move deeper into the cell (maybe all the way to the tail).

Opening is a very violent process during which the parachute expands from being in a bag approximately the size of a woman's purse to full flight which, depending on the parachute, can be anywhere from ~100 - 400 square feet.

My parachute is a Sabre 2 170 which means it is just under 20 feet wide and 7 feet deep.

This means that on opening, an object in the tail of the parachute would have to move forward 7 feet. Depending on the pitch of the canopy and what maneuvers I am executing, the combination of the angle and gravity could easily keep an object inside the canopy for more than 5 seconds. The object (even a good sized rock) would stay in there for the entire flight.

You have to also consider that this was a wingsuit deployment, which has different opening characteristics than a traditional vertical deployment because the jumper has much more forward velocity and less vertical velocity. This would affect the orientation of the canopy and would have an effect on how objects inside the canopy would move around.

I have personally seen grass and twigs come out of my canopy. I have seen a video from a friend who saw several socks come out of his nose as his canopy had been sitting unpacked next to a laundry basket the night before. Parachute riggers that do inspections or repairs on canopies have great stories of things they have found inside canopies including phones and drugs.

So while the meteorite story is exciting, the idea of a rock falling in your immediate airspace doesn't sound very impossible if you're a skydiver. I'd not call it common, but it's certainly not a rare occurrence. While not the most newsworthy, the simplest explanation is the guy packed a rock in his parachute and god knows how he didn't notice when he packed but it wouldn't be the first rock to take make a skydive.

While not the most newsworthy, the simplest explanation is the guy packed a rock in his parachute and god knows how he didn't notice when he packed but it wouldn't be the first rock to take make a skydive.

That's a long post, but it fails to address how the rock got to the speed of several hundred km per hour by the time it flew past him.

it fails to address how the rock got to the speed of several hundred km per hour by the time it flew past him

You can address it yourself. Gravitational acceleration is 9m/s^2. 300 km/h is 83m/s. The rock could have easily been going less than that, say 50m/s. It takes 6 seconds for it to accelerate to that speed from rest. It didn't start at rest.

You're missing the point. The skydiver is not at rest either. It is not traveling at the absolute speed of 300km/h, it is traveling 300 km/h faster than the diver. Go ahead and count the number of seconds between when he pops his chute, and when the rock flies by, and tell me if that is enough time for the rock to accelerate to a speed of 300km/h relative to the diver while still being above him.

What you're suggesting is that the rock would have had to have been launched directly upward at a relatively h

I have a hard time imagining a chute launching a rock that size high enough up to delay it that long, and of course the rock would have had a hard time getting that far forward to catch that weird gust of wind that brought it back toward the camera.I remember a bullet that did that and then landed on a guy's stretcher once, so it could happen. [wikipedia.org]

Yes, the apparent speed is the biggest argument against it being something packed in the 'chute, I'd think. If the skydiver were still decelerating hard after the parachute opened, the rock could appear to move rapidly, but even then it appears to come from farther away than the parachute.
I'm still looking into this, and will have my own thoughts posted tomorrow on my blog.

Thanks Phil. It would be interesting to see an analysis of the relative speed, it looks fairly difficult to do because it looks like the rock is coming in at an angle (although it's hard to tell without much of a frame of reference).

That analysis was done here: http://norskmeteornettverk.no/... [norskmeteornettverk.no] (it's not in English, but google translate does a decent job). He makes a distance estimate based on speed, which itself is based on the assumption it's a falling rock at terminal velocity. But the distance, speed, and time it takes to cross the FOV are related, and if you make a stab at speed you can get distance and vice versa.

If this thing is falling from the parachute, that would make it a small, nearby, slow object rather than a larger, faster object further away. Assuming a 7 m tall parachute (including lines, ) + 1 m more of skydiver legs below that, we find that the rock traveled from around the top of the parachute to definitely below the skydiver in 15 frames of video, which gives us a velocity of about 13 m/s relative to the skydiver. Assuming that the parachute has slowed the skydiver down to a landing velocity of 7 m/s

Notice in the video right before "the rock" flies past there is a spec in the distance too, lower left side of screen.
This may be another fragment of the same meteorite as it broke up and would support the "larger rock breaking up" theory.
It also fits with the fresh fracture-surface seen on the large object.

Consider that the description says "It rock zooms by at about:20 in this video:" (sic), when it's clearly another skydiver at that time. The meteor is at 0:15 (in the upper left window with the back camera view). In another video, a geologists tries to deduct some information about the meteor by looking at still frames extracted from the video: He clearly interprets compression artifacts (the ringing around sharp edges) as features of the meteor. Nobody appears to have taken rolling shutter into account ei

Actually you are probably right.
"My second rock" is most likely the other wingsuit diver far away still. It's in the slow motion part of the video about 2:12 right about the Y in the english translation text: "- Yes it's... My goodness."

What's with the obnoxious, non-mutable autoplay ad for this movie? Half the sites I visit are playing this, some times more than once on a page so it comes out garbled because the copies don't sync. This has to be one of the biggest Internet ad campaigns ever.

And since when does Slashdot carry ads that autoplay audio? That's low-rent stuff. The worst thing with this ad is that the player presents a mute button that doesn't mute, it starts the replay over again. The only thing you can do is mute your en

I did not get that, but I've commenced a Sears boycott since that full-volume commercial hijacked my computer at 3AM last week (it woke up two people that I know of, got the dog out of bed, and probably disturbed the downstairs neighbor.) I don't know how many others adhere to this, but I have a strict policy of depriving revenue to offensive businesses.

Sorry, I was referring to an ad served on Comedy Central, but I hold the client liable for the offense.

Fuck you, Sears.

OP was assaulted @ TFA, I was not, at this time, but its the sort of thing that would make me skip a movie I had planned to see in a theatre.I'm a petty, vindictive asshole; But really, do those guys think they're selling better?

Did nobody else see the bird fly past a second after the shiny rock....? His parachute was deployed, so he wasn't *that* high up. If I was a bird that just saw a man fall from an aeroplane and then explode into a giant jellyfish, I'd drop whatever shit I was carrying too.

Yeah, they're writing technical reports on shit that someone has packed into a chute. Oh, how easy it is for experts in field A to assume they have been born with knowledge from field B. Namely, those meteor experts who just don't get what every skydiver learns after a while: shit sometimes get packed into the chute. This whole thing is just so full of fail I don't know whether to laugh or cry.

I think it is most likely legit, or such an elaborate hoax that even the Norwegian state television fell for it while producing a pretty long report (linked by the AC responding to my GP post), which I think is very unlikely.

It's not exposed to atmospheric heat (from compression, not friction) for long enough. It's heated for seconds, and the heat is so intense that it blasts off outer layers instead of dispersing into the body -- which, remember, is at cryogenic temperatures when it hits the atmosphere.

The light from meteors is nearly all from compressed atmosphere and vaporized rock/metal. All the material that's hot enough to glow gets knocked off.

Burned out meteors have slowed down to terminal velocity (or close to it) so they would be going at a similar speed to a rock tossed from a plane, several times faster than the terminal velocity of a human, but only a few hundred meters per second, the video is within the plausible zone for speed. Pretty astonishing bit of video.